Subject: Re: BPF in linux-libre

From: Mathieu Othacehe <[email-masked]>
Date: Mon, 06 Jul 2020 15:26:11 +0200

Hey John,

> I think I tidied up the description to match the Guix situation. What do
> you think now?

Yes it's fine, thanks for the updated serie! I pushed the first patch
and patches two and three squashed together.

> I could see it being a useful default.  BPF seems like a nice technology
> but I am making these patches to experiment with it myself.  Because I
> haven't used it much I can't really speak on the pros of making it
> default.  Other than my gut feeling that seems like something that
> should be opted into rather than opting out of I have no strong feelings
> on including it by default.  The only other downside I see is that
> putting in the default might make the linux definitions less composable.
> The way it is now, one can assemble a (mostly) bpf-capable system from
> the pieces in gnu/packages/linux.scm.

Ok, thanks for explaining. I don't have much experience with BPF
either. For now we can work with a separate linux-libre, and will see
about merging it into the default, when we'll have more perspective.

I'll take more time to review patches 4 and 5. However, while trying
some of the examples packaged by BCC, I have the following error:

--8<---------------cut here---------------start------------->8---
mathieu@meru:~/guix-master$ /gnu/store/rv51f9n1w9i92m9qsg9k3ilsy3hyhjf3-bcc-0.15.0/share/bcc/tools/execsnoop
Traceback (most recent call last):
  File "/gnu/store/rv51f9n1w9i92m9qsg9k3ilsy3hyhjf3-bcc-0.15.0/share/bcc/tools/execsnoop", line 21, in <module>
    from bcc import BPF
ModuleNotFoundError: No module named 'bcc'
--8<---------------cut here---------------end--------------->8---

I think an additional wrapping is necessary. Could you please have a
look? I'm also removing help-guix, and opening a proper guix-patches
ticket.

Thanks,

Mathieu